Several different types of optical MEMS devices are known within the art.
A problem related to prior art optical MEMS devices, such as transmissive microshutter-based spatial light modulators (SLM) is that the various optical components of the individual microshutters must be arranged in mutually very well-defined positions in order to obtain the desired optical characteristics, e.g. of an optical path through the microshutter arrangement. Even small misalignments or variations in the mutual positioning between the optical components may result in reduced transmission.
A further problem of the optical transmissive microshutter MEMS devices is that moving parts of the devices typically must be encapsulated in order to reduce influence from e.g. dust and humidity. This encapsulation is often obtained by encapsulating the complete mechanical system between the input and the output optics, e.g. micro lenses. One way of encapsulation is obtained by applying so-called spacer glue in order to obtain the necessary distance between the micro lenses and the other structural parts and subsequently applying a surrounding sealing. A problem related to this encapsulation is, however, that the prior art encapsulation process is expensive and not always sufficient for obtaining a reliable end product.
It is an object of the invention to provide a well-defined positioning of the optical components of an optical MEMS device.
It is a further object of the invention to provide an optical MEMS device, in particular an optically transmissive MEMS device having improved properties with respect to sealing.